title: Bovine pancreatic DNase I binds very tightly to DNA fragments and may be mistaken for putative endogenous nuclear proteins covalently bound to DNA.
abstract: Using published methods for the isolation of nuclear proteins tightly bound to DNA, and resistant to removal by SDS or 16-BAC detergent and urea, several new protein bands in the region of 55 kd and 62 kd on SDS gel and 43 kd and 70 kd on 16--BAC gel electrophoresis were identified in extracts of avian erythroid nuclei. These bands were radiolabelled by subjecting the DNA--protein complexes to nick--translation in the presence of [32P]--dCTP, followed by prolonged digestion with excess bovine DNase I. Amino acid sequence analysis shows that these bands contain DNase I. These results indicate that DNase I can form stable complexes with DNA, and suggest that DNase I--DNA complexes may be mistakenly identified as nuclear proteins covalently bound to DNA.
authors.affiliation: Department of Internal Medicine, University of Iowa, Iowa City.
authors.forename: T W
authors.initials: TW
authors.lastname: Brotherton
authors.forename: D W
authors.initials: DW
authors.lastname: Zenk
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002645:Chickens; D004247:DNA / Q000097:blood / Q000302:isolation & purification / Q000378:metabolism*; D003850:Deoxyribonuclease I / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010179:Pancreas / Q000201:enzymology*; D011485:Protein Binding; D014176:Protein Biosynthesis; D012156:Reticulocytes / Q000378:metabolism
chemical_list: D009687:Nuclear Proteins; D004247:DNA; D003850:Deoxyribonuclease I